The US, seeking a record fifth straight World Cup crown, fought back from five runs down to defeat hosts South Korea at Gijang-Hyundai Dream Ballpark.

South Korea made a promising start before the American team recovered to clinch an 8-5 win in a weather-affected contest.

It sent the US through to tomorrow's final, where they will bid to continue their dominance of the World Baseball Softball Confederation event.

Their opponents will be Chinese Taipei, who finished second in the super round phase.

Chinese Taipei's spot in the gold medal match was already secured when they took on Canada, who ran out 12-7 winners to claim their first victory in the super round.

Japan, ranked number one in the world at under-18 level, will not compete for a medal after they were stunned by Australia.

The Australian side recorded a shock 4-1 triumph to finish third and seal a berth in the bronze medal match against South Korea.

The tournament concludes with the two medal matches tomorrow.